As depicted in FIGS. 1 and 2 a presentation system employs a window 2 in order to provide a rectangular view of all, or a portion of all, of an application presentation space 1. When displayed on a physical screen 3 the window 2 may be provided with an identifying title block 4, it being realized that some arbitrarily large number of windows may be simultaneously displayed to a user. In order to be effectively employed the window 2 must be capable of being moved, or scrolled, in a vertical and/or a horizontal direction within the presentation space 2. A scrollbar 5 is a well known structure used to visualize the movement of the window 2 over the presentation space 1. An example of a system that employs scrollbars in this manner is the OS/2 Presentation Manager (OS/2 is a registered trademark of the International Business Machines Corporation and Presentation Manager is a trademark of the International Business Machines Corporation).
The scrollbar 5 is often used in conjunction with a pointing device, such as a mouse or a trackball. When the window 2 is too small in either the horizontal or vertical dimension, relative to the dimensions of the presentation space 1, the scrollbar 5 is presented to the user. The vertically disposed scrollbar 5 of FIG. 2 can be seen to contain a slider 6 which is moved with the pointing device in the directions indicated by the direction indicator blocks 7 and 8. As the slider 6 is moved by the user in the desired direction the relative position of the window 2 on the presentation space 1 is moved accordingly. This provides a rapid and efficient method for the user to vertically and/or horizontally scroll the window 2 through the presentation space 1. Many applications that present information on a display utilize this technique to good advantage. Examples of applications using scrollbars are text editors, spread sheets and graphics applications.
The only location information provided by the conventional scrollbar 5 is the relative distance of the window 2 from the edge (top and bottom or left and right) of the presentation space 1. A problem occurs when the window 2 only covers a relatively small area of the presentation space 1 and the user wishes to scroll to specific information within the presentation space 1. This is a common problem which pre-dates the use of modern window systems. For example, by using a word processor a user can edit a very large text file. To locate a specific location within the file the user can inefficiently read through the file, scrolling as necessary. A more efficient technique is for the user to issue a "search" command to automatically search for an occurrence or occurrences of "relatively unique" information. However, if relatively unique information does not exist in the appropriate form or is unknown to the user this latter technique cannot be effectively used. Other methods have also been developed for locating information. For example, if the user determines that locating a specific item of information in the future may be important he may place a "bookmark" at the corresponding location within the file. The bookmark is a program-provided feature employed to subsequently locate the desired information.
The following chronologically ordered U.S. Patents all teach display-related subject matter. In U.S. Pat. No. 4,247,843, issued Jan. 27, 1981, Miller et al. disclose in an avionics application a CRT display that displays an array of major cells and a map memory having map words corresponding to the cells. In U.S. Pat. No. 4,716,404, issued Dec. 29, 1987, Tabata et al. disclose an image retrieval method that includes a step of specifying a sub-image associated with a stored image, the stored image having stored reference data associated therewith. In U.S. Pat. No. 4,734,689, issued Mar. 29, 1988, Kurakake discloses display apparatus that enables a screen to scroll while a cursor is maintained in a readily visible position. In U.S. Pat. No. 4,772,882, issued Sep. 20, 1988 Mical discloses menu item selection performed with a mouse. In U.S. Pat. No. 4,780,709, issued Oct. 25, 1988, Randall discloses a display management system that is said to allow data to be read from window buffers directly onto a visual display without first compiling a bit map frame buffer. In U.S. Pat. No. 4,782,397, issued Nov. 1, 1988, Kimoto discloses image data processing apparatus that includes an edit function. And, in U.S. Pat. No. 4,786,897, issued Nov. 22, 1988, Takanashi et al. disclose a "jumpscroll-icon" used to change a displayed portion of a logical screen.
In a Research Disclosure, dated January 1989, there is disclosed anonymously a visual scaling technique that has a "visual scale" displayed adjacent to a scrollbar. The visual scale is said to provide quantitative point of reference information for end users. This disclosure also states that the visual scaling technique can be used with other forms of scrolling mechanisms or as a scrolling technique "in its own right" that is apparently without a scrollbar.
However none of these references teach, and it is thus an object of the invention to provide, presentation space-related location indicia within a scrollbar; the indicia being generated by a data processing system and/or by a user of the system.
It is a further object of the invention to provide an improved scrollbar and method of using same that has enhanced utility and enhanced human factors characteristics relative to conventional scrollbars.
It is another object of the invention to provide presentation space-related location information within a scrollbar having greater efficiency for the case where the presentation space is significantly larger than a window size.
It is another object of the invention to provide presentation space-related location information within a scrollbar, the location information being dynamically changeable as a function of a physical size of the scrollbar, the relative area of the window to the presentation space and an amount of location information.
It is a still further object of the invention to provide presentation space-related location information within a scrollbar, the location information having the form of, by example, characters, symbols, graphics, color and/or audio cues.